A wireless transmission system using microwaves or millimeter waves is generally used to connect a base station to a mobile backhaul network. Wireless connection between a base station and a mobile backhaul network has advantages over wired connection using optical fibers in easy network construction, high economic efficiency, and low constraints on the installation location of the base station.
A mobile backhaul network is an upper-level network to which a base station is connected. The mobile backhaul network includes, for example, a control node that performs signaling with a base station and a mobile station, a switching node that processes voice calls, and a transfer node that performs data transfer. Typically, the mobile backhaul network is managed by a mobile telecommunications carrier (a mobile operator). The mobile backhaul network includes a core network and, in some architecture, further includes a radio access network node. For example, in the case of UTRAN (UMTS Terrestrial Radio Access Network), the mobile backhaul network includes an RNC (Radio Network Controller) and a core network (e.g., a SGSN (Serving GPRS Support Node), a GGSN (Gateway GPRS Support Node), and an MSC (Mobile Switching Center)). Further, in the case of E-UTRAN (Evolved UTRAN), the mobile backhaul network includes a core network (e.g., an MME (Mobility Management Entity), an S-GW (Serving Gateway), and a P-GW (PDN Gateway)).
For example, Patent Literature 1 is known which describes a wireless transmission device for connecting a base station to a mobile backhaul network. Patent Literature 1 discloses a microwave wireless transmission device that includes an antenna and a front-end device (ODU: Outdoor Unit) installed outdoors and a back-end device (IDU: Indoor Unit) installed indoors. The front-end device (ODU) primarily performs analog signal processing such as frequency up/down conversion and amplification. The back-end device primarily performs digital signal processing such as channel coding/decoding, interleaving/deinterleaving, and modulation/demodulation.